Scummer for settling tanks and the like



i I Dec. 14, 1937. S/SHAFER, JR 2,102,575,

- SCUMMER F'OR SETTLING TANKS AND THE LIKE I h Filed Aug. 7, 1935 3Sheets-Shee t 1 Mow/m p Dec. 14, 1937. s. SHAFER, JR

SGUMMER FOR SETTLING TANKS AND THE LIKE Filed Aug. 7,1955 a Sheets-sheaf2 Dec. 14,1937. r -s.'sHA-F -R,'JR 2,102,575-

SC'UMMER F05 SET'ILING, TANKS AND THE LIKE Filed Aug. 7, 1955 sSheets-Sheet, s

Patented Dec. 14, 1937 "UNITED STATES PATENT! oFF cE;

SCUMMER FOR SETTLING TANKS AND THE LIKE

Samuel Shafer, Jr., Milwaukee, Wis., assignor to ChainBelt Company,poration of Wisconsin be simple in construction,comparativelyinexpensive to manufacture and install, and more efiicientin use than those which have been herejtofore'proposed.

' In various liquid separation and purification operations, of which thehandling of raw sewage may be cited as one typical example, it iscustomary to provide relatively large tanks or receptacles into whichare introduced liquids bearing light and heavy solids. The liquid ismain tained in the tanks in a relatively quiescent state, to the endthat the heavier solids may settle and form a sludge which is'eitherconstantly or intermittently removed from the bottom of the tank byvarious mechanisms. In many instances, certain of the lighter solids areso light as to float upon the liquid surface and refuse to settle,'andin order that the maximum degree of separation or purification may beattained, it is necessary to provide means for skimming such floatingdebris from the liquid surface. v r The'present invention relates tothis latter class of apparatus, and in its preferred embodimentcomprises ajcarriaga. preferably motor driven, mounted for movement toand fro above the surface of the liquid in the tank, which carriage isprovided with a scum blade extending downwardly to slightly below theliquid surface, and mounted for vertical movements relative to thecarriage. One or more scum-receiving troughs or receptacles are providedin the path of travel of the said blade, such troughs having portionsboth above and below the liquid level; and the relation of the parts issuch that'as the blade reaches the trough, its lower edge engages andrides up an inclined wing thereof, pushing the scum and/or 1 floatingdebris into the trough. The troughs may be provided with'spaced bridgemembers for supporting the blade and preventing it from dropping intothe trough, although permitting itto deposit "the scum therein.

The invention is susceptible of use in a single tank, or in connectionwith a battery of tanks, and for purposes of disclosure'has been hereillustrated-in both forms.

With the above and other objects in view which will appear as thedescription'proceeds, the invention consists in the novel details ofconstruction and combinations of parts more fully'hereinafter. describedand particularly pointed out in the appended claims.

Referring more particularly to the accompany- Milwaukee, Wis., a cor-1935', Serial No. 35,187

ing drawings forming part of this specification,

inwhich like reference characters designatelike parts in all the views:-r Figure 1 is a'longitudinalsectional elevational view of a preferredembodimentof the scumming apparatuataken approximately ontheplaneindicated by the line' Il of Fig. 2, looking in the direction ofthe arrows;

Fig. 2 is a transverse sectional elevational view, approximately on theplane indicated by the line 2-4 of Fig. 1, looking in the direction ofthe ar- I'OWS Fig.3 is an enlarged horizontal sectional View, 7

approximately on the plane indicated'by the line 33 of Fig. 1, lookingdown; I

Fig. 4 is a fragmentary view but taken approximately on theplane indieby the line 4-4 of Fig. 1;

Fig. 5 is a fragmentary plan view, illustrating the mechanism forreversing the carriage travel;

Fig. 6 is a diagrammatic fragmentary translverse sectional view,illustrating the use of the ,scummer with a battery of settling tanks;

Figj'l is a fragmentary longitudinal sectional view of the upper part ofa single settling tank equipped with the scumming apparatus of thisinvention; and

Fig. 8 is a transverse sectional view taken on the plane indicated bythe line 8-8 of Fig. 7, looking in the direction of the arrows.

Referring first more particularly to Fig. 6, there is illustrated aseparation or purification installation comprising a battery ofsedimentation tanks l0 disposed side by side. Each of these tanks may beprovided with sludge removing'apparatus of any suitable character, suchfor example, as the endless belt and scraper type shown in the prior U.S. Patent No. 1,990,458, granted February 5, 1935, to William B.Marshall. This type of V apparatus--which in itself constiated similarto'Fig. 3, T

tutesfno part of the present invention, and there fore has notbeenillustratednot only scrapes the settled heavy-solid sludge to oneend" of the tank bottoms whereit may be drawn off, but the upper-run ofthe conveyor is so arranged at the liquid level that the scraper flightsmove the scum and floating debris to the other end of the tanks, whereit may be transferred by appropriatemechanisnr to scum receptacles. V

' When used with an installation of this charter, the present inventionis preferably arranged a metal troughs l2 mounted at the top of certainof the dividing walls l3 between adjacent tanks and/or upon the extremesidewalls 14. The said scum troughs are preferably positioned atsubstantially the liquid level, which may vary some down which thescummer blade to be hereafter described may slide. The troughs arealsopreferably provided with the narrow spaced'straps" or bridge;members I8 spanning them from side to side, which not only brace thetroughs themselves, but also support the scumblade as it travels acrossthe troughs and preventit from dropping thereinto. r

The scumming apparatus constituting the gist of the present invention,as best shown in Figs. 1

and 2, comprises a carriage provided with suit ableisupporting andtraction wheels 2| running .upon.rails 22 mounted upon the upper'surfaceopposite sides of the gear 24'so as to be driven in opposite directionsthereby. The said gears 25 and 26 are loosely mounted upon acountershaft 2 1 and they are respectively provided with clutch members28 and 29 which are adapted to be alternately engaged-by the companionclutch members 7 30 and 3| 'of a collar 32 which is splined to the.shaft 21. A'shifting 1ever'33 is pivoted as at 34 to the carriageframework and one end thereof engages a groove 35 provided on the collar32 whilethe other end of the said lever-is arranged to be moved back andforth by a rod or plunger 36 which constitutes the armature for apair ofsolenoids 31 and 38. These solenoids are adapted to be alternatelyenergized in any suitable manner by either manual or automatic control,and as will bereadily understood, when one of them, as for example; thesolenoid 38, is energized the clutch shifting lever 33 will be moved tothe position shownin Figure 5, wherein the clutch members 28 and 30 areengaged while the clutch mem-, bers 29 and 3| are disengaged so thatthepower from the motor 23 will be transmitted through gears 24 and 25 andcollar 32 to the shaft 21 to rotate the .latter in a predetermineddirection. On

theother hand when the solenoid 31 is energized and the solenoid; 38 isdeenergized, the clutch will'be shifted to provide a drive through'gears24 and 26 wherebyjthe direction of rotation of shaft 2! will bereversed.

' Said shaft 21 is provided with a sprocket 40 around which passes thesprocket chain 4| which also engages the sprocket 42 carried by theshaftor axle 43 upon which one pair of the supporting wheels 2| is mountedwhereby traction may be supplied for the carriage and thelatter causedto move. upon the rails 22. Depending from either side of thecarriageframe is a pair of spaced vertical; angle members 45 which aremaintained in spaced relation by suitablebraces 46, see Fig. '1,andwhich angle members carry suitable guiding rolls 4! and 4 6; Aswillbe clear from Figure 3,

the rolls 4'! are preferably of the grooved type,

As best shown in Figs; 1 and 6' .usualjmannfer. V V

riage and blade will cause the latter to ride across flanges 49 ofvertically'disposed 'T-members 50. The'said T-members are connectedtogether at their upper ends by a transverse member 5! to maintain themin spaced relation, and at their lower. ends are secured to the scummerblade 52 .which extends between them as will be clear from Figs. 1 and2; JIhis blademay'beof any suitable what, within the limits indicated bythe broken lines l5 and I6 in Fig. 1; and they are provided with thelateral inclined wings l1, extending from; below to above the saidliquid level, and up and construction, but'i't is preferredto make it ofsheet aluminum in substantially the'form shown :in said Figs. 1 and 2.

. The transverse frame member 5| has secured 'to it a cable or chain 53which passes upwardly the grooves thereof being engaged by the head overa pulley 54 suitably journalled upon the carriage frame, and the otherend of thesaid chain. or cable 53 has-attached to it a suitablecounter-:

weight 55, see Fig. 1, which partially .but not completelycounter'balanc'es'the weight of the blade 52 arid-its frame members .50and 5|; The blade is thus free to move vertically under the influence ofgravity with its frame members 56 being guided. by the grooved rolls41,,and with the plain rolls 48 bearing upon the flat surface of'theblade as will be readily understood from Figs. 1 and 2.. "Electriccurrent for the operation of the motor mechanism 63 and with a magneticstarting mechanism 64 for controlling the motor 23, all of whichmechanism may be of anyusual and wellknown construction and in itselfconstitutes no partj of the present invention.

7 The operation o'fthe 'scummer will bereadily it will drive the;carriage along therails .22 in one direction .or the otherdepending uponwhich pair of the clutch members 28, 29,30,13I are engaged. The scummerblade .52 will normally occupy a positionsuch as shown in Figs. 1 and 2,with its loweredge somewhat below the surface of the ,liquid 'withinthetanks 'andas' it is-moved along vby the carriage it will, of course,transfer the scum and debris floating upon the surface of the 'trough l2from which itmayflow into any suitable receptacle or be otherwisedisposed of inthe Continued movement of the car- {23 may be supplied bysuitable conductors 60 supported at one sideof the trackwayand may zbetransferred to the carriage 20 by suitable sliding contacts 6 I, carriedby a trolley arm 62. The carriage may be provided with a suitable pushbutton 30 I apparent 'fromthe' foregoing, it. being'understood 1 thatupon current being supplied to the motor 23 the strap or bridge membersl8 and down the oppositeinclined Wing l1 to bring its lower edge againbelow the liquid surface. -When the carriage reaches the extreme sideofthe. battery of tanks theappropriate solenoid 31 or 38'wi1l beenergized, usuallyautomatically, to reverse the .carriagemotion and thescumming operation will be repeatedduring the return travel ofthecarriage.

,,While the invention has been thusillustrated in 1 Figs. 1 to fiinclusive' and described as applied to V a battery of tanks, it will beobvious that the scummermay bealso applied to a single tank,

bers 45 depend from the carriage 26 immediately adjacent the side walls65, of the tank'and' carry the rolls 4'! and 48 guiding the scummerblade 52 75 which extends substantially from wall to wall. It istherefore obvious that various changes may be made in the details ofconstruction and precise arrangement of the parts without departing fromthe spirit of the invention and it is not wished to be limited to theabove disclosure except as may be required by the claims.

' What I claim is:

1. In sedimentation apparatus and the like, a plurality of tanksarranged side by side; scum receiving troughs carried by the divisionwalls of said tanks; and a reciprocating scumming device arranged totransversely traverse all of said tanks, and to successively pass overand deposit scum in said troughs.

2'. In apparatus for removing accumulating scum from a plurality ofsettling tanks, a common division wall separating adjacent tanks; a scumtrough supported above the level of liquid in the tanks by said divisionwall and arranged to receive scum from either tank adjacent thereto;

and a single scum collecting instrumentality arranged to successivelycollect accumulating scum from the surface of the liquid in said tanksand to pass the scum alternately from each adjacent tank to said scumtrough.

3. In scum removing apparatus for settling tanks and the like which areprovided with scum receiving receptacles, a mobile carriage arranged forhorizontal travel above the surface of the liquid in the tank; framemembers depending perpendicularly from said carriage adjacent eitherSAMUEL SHAFER, JR.

